Scientists are building up a photographic database of the rare and endangered natterjack toad, in a bid to ensure its survival in Scotland.

They are relying on each toad's unique pattern of warts to enable them to identify individual animals.

That information will then be used by researchers monitoring whether the population rises or falls in the coming years.

The work is being carried out along the Solway Firth.

The toads can be found on sand dunes and in salt marshes known as merse.

Natterjack toads

Natterjack toads are Scotland's rarest amphibians

In Scotland, they are only found on the Solway Firth

There are thought to be around 200 breeding adults in Scotland

The toads are a grey green colour and have a distinctive yellow stripe on their backs

Natterjacks have shorter legs than common toads or frogs

This means they can run after prey, rather than hopping or crawling

During the breeding season, croaking male natterjacks can be heard more than a mile away

The scientists search the area after dark, using torchlight to find the natterjacks.

The toads are then measured and photographed.

James Silvey of RSPB Scotland said: "The beautiful thing about natterjacks is they each come with their own individual fingerprint, and that's in the form of the big warts and the yellow stripe on their backs.

"Each of the toads we photograph today could potentially live for 10 or 15 years and if we photograph it again we'll know that individual was found here at Mersehead in 2014.

"We're building up a database of natterjack mug shots for the future."

Conservationists have been working for many years to safeguard the future of the species in Scotland.

They say natterjacks face several threats, including habitat loss, climate change and a fungal infection first identified in 1999.

Image copyrightDawn NicollImage caption
James Silvey, left, and Pete Minting are leading the study

A population of natterjacks was established at the RSPB Mersehead nature reserve near Dalbeattie in the same year.